]> arthur.barton.de Git - netdata.git/blobdiff - src/web_client.c
registry server side operational
[netdata.git] / src / web_client.c
old mode 100755 (executable)
new mode 100644 (file)
index 1fd41a1..c4199b5
@@ -1,6 +1,6 @@
-// enable strcasestr()
-#define _GNU_SOURCE
-
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
 #include <unistd.h>
 #include <stdlib.h>
 #include <sys/types.h>
 #include <fcntl.h>
 #include <netinet/tcp.h>
 #include <malloc.h>
+#include <pwd.h>
+#include <grp.h>
+#include <ctype.h>
 
 #include "common.h"
 #include "log.h"
-#include "config.h"
+#include "appconfig.h"
 #include "url.h"
 #include "web_buffer.h"
 #include "web_server.h"
 #include "global_statistics.h"
 #include "rrd.h"
 #include "rrd2json.h"
+#include "registry.h"
 
 #include "web_client.h"
+#include "../config.h"
 
-#define INITIAL_WEB_DATA_LENGTH 65536
+#define INITIAL_WEB_DATA_LENGTH 16384
+#define WEB_REQUEST_LENGTH 16384
+#define TOO_BIG_REQUEST 16384
 
 int web_client_timeout = DEFAULT_DISCONNECT_IDLE_WEB_CLIENTS_AFTER_SECONDS;
 int web_enable_gzip = 1;
 
+extern int netdata_exit;
+
 struct web_client *web_clients = NULL;
 unsigned long long web_clients_count = 0;
 
 struct web_client *web_client_create(int listener)
 {
        struct web_client *w;
-       
+
        w = calloc(1, sizeof(struct web_client));
        if(!w) {
                error("Cannot allocate new web_client memory.");
@@ -93,9 +102,28 @@ struct web_client *web_client_create(int listener)
                if(setsockopt(w->ifd, SOL_SOCKET, SO_KEEPALIVE, (char *) &flag, sizeof(int)) != 0) error("%llu: Cannot set SO_KEEPALIVE on socket.", w->id);
        }
 
-       w->data = web_buffer_create(INITIAL_WEB_DATA_LENGTH);
-       if(unlikely(!w->data)) {
+       w->response.data = buffer_create(INITIAL_WEB_DATA_LENGTH);
+       if(unlikely(!w->response.data)) {
+               // no need for error log - web_buffer_create already logged the error
+               close(w->ifd);
+               free(w);
+               return NULL;
+       }
+
+       w->response.header = buffer_create(HTTP_RESPONSE_HEADER_SIZE);
+       if(unlikely(!w->response.header)) {
+               // no need for error log - web_buffer_create already logged the error
+               buffer_free(w->response.data);
+               close(w->ifd);
+               free(w);
+               return NULL;
+       }
+
+       w->response.header_output = buffer_create(HTTP_RESPONSE_HEADER_SIZE);
+       if(unlikely(!w->response.header_output)) {
                // no need for error log - web_buffer_create already logged the error
+               buffer_free(w->response.header);
+               buffer_free(w->response.data);
                close(w->ifd);
                free(w);
                return NULL;
@@ -112,6 +140,72 @@ struct web_client *web_client_create(int listener)
        return(w);
 }
 
+void web_client_reset(struct web_client *w)
+{
+       struct timeval tv;
+       gettimeofday(&tv, NULL);
+
+       long sent = (w->mode == WEB_CLIENT_MODE_FILECOPY)?w->response.rlen:w->response.data->len;
+
+#ifdef NETDATA_WITH_ZLIB
+       if(likely(w->response.zoutput)) sent = (long)w->response.zstream.total_out;
+#endif
+
+       long size = (w->mode == WEB_CLIENT_MODE_FILECOPY)?w->response.rlen:w->response.data->len;
+
+       if(likely(w->last_url[0]))
+               log_access("%llu: (sent/all = %ld/%ld bytes %0.0f%%, prep/sent/total = %0.2f/%0.2f/%0.2f ms) %s: %d '%s'",
+                       w->id,
+                       sent, size, -((size>0)?((float)(size-sent)/(float)size * 100.0):0.0),
+                       (float)usecdiff(&w->tv_ready, &w->tv_in) / 1000.0,
+                       (float)usecdiff(&tv, &w->tv_ready) / 1000.0,
+                       (float)usecdiff(&tv, &w->tv_in) / 1000.0,
+                       (w->mode == WEB_CLIENT_MODE_FILECOPY)?"filecopy":((w->mode == WEB_CLIENT_MODE_OPTIONS)?"options":"data"),
+                       w->response.code,
+                       w->last_url
+               );
+
+       debug(D_WEB_CLIENT, "%llu: Reseting client.", w->id);
+
+       if(unlikely(w->mode == WEB_CLIENT_MODE_FILECOPY)) {
+               debug(D_WEB_CLIENT, "%llu: Closing filecopy input file.", w->id);
+               close(w->ifd);
+               w->ifd = w->ofd;
+       }
+
+       w->last_url[0] = '\0';
+       w->cookie[0] = '\0';
+
+       w->mode = WEB_CLIENT_MODE_NORMAL;
+
+       buffer_reset(w->response.header_output);
+       buffer_reset(w->response.header);
+       buffer_reset(w->response.data);
+       w->response.rlen = 0;
+       w->response.sent = 0;
+       w->response.code = 0;
+
+       w->wait_receive = 1;
+       w->wait_send = 0;
+
+       w->response.zoutput = 0;
+
+       // if we had enabled compression, release it
+#ifdef NETDATA_WITH_ZLIB
+       if(w->response.zinitialized) {
+               debug(D_DEFLATE, "%llu: Reseting compression.", w->id);
+               deflateEnd(&w->response.zstream);
+               w->response.zsent = 0;
+               w->response.zhave = 0;
+               w->response.zstream.avail_in = 0;
+               w->response.zstream.avail_out = 0;
+               w->response.zstream.total_in = 0;
+               w->response.zstream.total_out = 0;
+               w->response.zinitialized = 0;
+       }
+#endif // NETDATA_WITH_ZLIB
+}
+
 struct web_client *web_client_free(struct web_client *w)
 {
        struct web_client *n = w->next;
@@ -123,7 +217,9 @@ struct web_client *web_client_free(struct web_client *w)
 
        if(w == web_clients) web_clients = w->next;
 
-       if(w->data) web_buffer_free(w->data);
+       if(w->response.header_output) buffer_free(w->response.header_output);
+       if(w->response.header) buffer_free(w->response.header);
+       if(w->response.data) buffer_free(w->response.data);
        close(w->ifd);
        if(w->ofd != w->ifd) close(w->ofd);
        free(w);
@@ -133,26 +229,90 @@ struct web_client *web_client_free(struct web_client *w)
        return(n);
 }
 
+uid_t web_files_uid(void)
+{
+       static char *web_owner = NULL;
+       static uid_t owner_uid = 0;
+
+       if(unlikely(!web_owner)) {
+               web_owner = config_get("global", "web files owner", config_get("global", "run as user", ""));
+               if(!web_owner || !*web_owner)
+                       owner_uid = geteuid();
+               else {
+                       // getpwnam() is not thread safe,
+                       // but we have called this function once
+                       // while single threaded
+                       struct passwd *pw = getpwnam(web_owner);
+                       if(!pw) {
+                               error("User %s is not present. Ignoring option.", web_owner);
+                               owner_uid = geteuid();
+                       }
+                       else {
+                               debug(D_WEB_CLIENT, "Web files owner set to %s.\n", web_owner);
+                               owner_uid = pw->pw_uid;
+                       }
+               }
+       }
+
+       return(owner_uid);
+}
+
+gid_t web_files_gid(void)
+{
+       static char *web_group = NULL;
+       static gid_t owner_gid = 0;
+
+       if(unlikely(!web_group)) {
+               web_group = config_get("global", "web files group", config_get("global", "web files owner", ""));
+               if(!web_group || !*web_group)
+                       owner_gid = getegid();
+               else {
+                       // getgrnam() is not thread safe,
+                       // but we have called this function once
+                       // while single threaded
+                       struct group *gr = getgrnam(web_group);
+                       if(!gr) {
+                               error("Group %s is not present. Ignoring option.", web_group);
+                               owner_gid = getegid();
+                       }
+                       else {
+                               debug(D_WEB_CLIENT, "Web files group set to %s.\n", web_group);
+                               owner_gid = gr->gr_gid;
+                       }
+               }
+       }
+
+       return(owner_gid);
+}
+
 int mysendfile(struct web_client *w, char *filename)
 {
        static char *web_dir = NULL;
-       if(!web_dir) web_dir = config_get("global", "web files directory", "web");
 
-       debug(D_WEB_CLIENT, "%llu: Looking for file '%s'...", w->id, filename);
+       // initialize our static data
+       if(unlikely(!web_dir)) web_dir = config_get("global", "web files directory", WEB_DIR);
+
+       debug(D_WEB_CLIENT, "%llu: Looking for file '%s/%s'", w->id, web_dir, filename);
 
        // skip leading slashes
        while (*filename == '/') filename++;
 
        // if the filename contain known paths, skip them
-                if(strncmp(filename, WEB_PATH_DATA       "/", strlen(WEB_PATH_DATA)       + 1) == 0) filename = &filename[strlen(WEB_PATH_DATA)       + 1];
-       else if(strncmp(filename, WEB_PATH_DATASOURCE "/", strlen(WEB_PATH_DATASOURCE) + 1) == 0) filename = &filename[strlen(WEB_PATH_DATASOURCE) + 1];
-       else if(strncmp(filename, WEB_PATH_GRAPH      "/", strlen(WEB_PATH_GRAPH)      + 1) == 0) filename = &filename[strlen(WEB_PATH_GRAPH)      + 1];
-       else if(strncmp(filename, WEB_PATH_FILE       "/", strlen(WEB_PATH_FILE)       + 1) == 0) filename = &filename[strlen(WEB_PATH_FILE)       + 1];
+       if(strncmp(filename, WEB_PATH_FILE "/", strlen(WEB_PATH_FILE) + 1) == 0) filename = &filename[strlen(WEB_PATH_FILE) + 1];
+
+       char *s;
+       for(s = filename; *s ;s++) {
+               if( !isalnum(*s) && *s != '/' && *s != '.' && *s != '-' && *s != '_') {
+                       debug(D_WEB_CLIENT_ACCESS, "%llu: File '%s' is not acceptable.", w->id, filename);
+                       buffer_sprintf(w->response.data, "File '%s' cannot be served. Filename contains invalid character '%c'", filename, *s);
+                       return 400;
+               }
+       }
 
-       // if the filename contains a / or a .., refuse to serve it
-       if(strchr(filename, '/') != 0 || strstr(filename, "..") != 0) {
+       // if the filename contains a .. refuse to serve it
+       if(strstr(filename, "..") != 0) {
                debug(D_WEB_CLIENT_ACCESS, "%llu: File '%s' is not acceptable.", w->id, filename);
-               web_buffer_printf(w->data, "File '%s' cannot be served. Filenames cannot contain / or ..", filename);
+               buffer_sprintf(w->response.data, "File '%s' cannot be served. Relative filenames with '..' in them are not supported.", filename);
                return 400;
        }
 
@@ -163,15 +323,33 @@ int mysendfile(struct web_client *w, char *filename)
        // check if the file exists
        struct stat stat;
        if(lstat(webfilename, &stat) != 0) {
-               error("%llu: File '%s' is not found.", w->id, webfilename);
-               web_buffer_printf(w->data, "File '%s' does not exist, or is not accessible.", filename);
+               debug(D_WEB_CLIENT_ACCESS, "%llu: File '%s' is not found.", w->id, webfilename);
+               buffer_sprintf(w->response.data, "File '%s' does not exist, or is not accessible.", webfilename);
                return 404;
        }
 
-       // check if the file is owned by us
-       if(stat.st_uid != getuid() && stat.st_uid != geteuid()) {
-               error("%llu: File '%s' is owned by user %d (I run as user %d). Access Denied.", w->id, webfilename, stat.st_uid, getuid());
-               web_buffer_printf(w->data, "Access to file '%s' is not permitted.", filename);
+       // check if the file is owned by expected user
+       if(stat.st_uid != web_files_uid()) {
+               error("%llu: File '%s' is owned by user %d (expected user %d). Access Denied.", w->id, webfilename, stat.st_uid, web_files_uid());
+               buffer_sprintf(w->response.data, "Access to file '%s' is not permitted.", webfilename);
+               return 403;
+       }
+
+       // check if the file is owned by expected group
+       if(stat.st_gid != web_files_gid()) {
+               error("%llu: File '%s' is owned by group %d (expected group %d). Access Denied.", w->id, webfilename, stat.st_gid, web_files_gid());
+               buffer_sprintf(w->response.data, "Access to file '%s' is not permitted.", webfilename);
+               return 403;
+       }
+
+       if((stat.st_mode & S_IFMT) == S_IFDIR) {
+               snprintf(webfilename, FILENAME_MAX+1, "%s/index.html", filename);
+               return mysendfile(w, webfilename);
+       }
+
+       if((stat.st_mode & S_IFMT) != S_IFREG) {
+               error("%llu: File '%s' is not a regular file. Access Denied.", w->id, webfilename);
+               buffer_sprintf(w->response.data, "Access to file '%s' is not permitted.", webfilename);
                return 403;
        }
 
@@ -182,158 +360,575 @@ int mysendfile(struct web_client *w, char *filename)
 
                if(errno == EBUSY || errno == EAGAIN) {
                        error("%llu: File '%s' is busy, sending 307 Moved Temporarily to force retry.", w->id, webfilename);
-                       snprintf(w->response_header, MAX_HTTP_HEADER_SIZE, "Location: /" WEB_PATH_FILE "/%s\r\n", filename);
-                       web_buffer_printf(w->data, "The file '%s' is currently busy. Please try again later.", filename);
+                       buffer_sprintf(w->response.header, "Location: /" WEB_PATH_FILE "/%s\r\n", filename);
+                       buffer_sprintf(w->response.data, "The file '%s' is currently busy. Please try again later.", webfilename);
                        return 307;
                }
                else {
                        error("%llu: Cannot open file '%s'.", w->id, webfilename);
-                       web_buffer_printf(w->data, "Cannot open file '%s'.", filename);
+                       buffer_sprintf(w->response.data, "Cannot open file '%s'.", webfilename);
                        return 404;
                }
        }
 
        // pick a Content-Type for the file
-                if(strstr(filename, ".html") != NULL)  w->data->contenttype = CT_TEXT_HTML;
-       else if(strstr(filename, ".js")   != NULL)      w->data->contenttype = CT_APPLICATION_X_JAVASCRIPT;
-       else if(strstr(filename, ".css")  != NULL)      w->data->contenttype = CT_TEXT_CSS;
-       else if(strstr(filename, ".xml")  != NULL)      w->data->contenttype = CT_TEXT_XML;
-       else if(strstr(filename, ".xsl")  != NULL)      w->data->contenttype = CT_TEXT_XSL;
-       else if(strstr(filename, ".txt")  != NULL)  w->data->contenttype = CT_TEXT_PLAIN;
-       else if(strstr(filename, ".svg")  != NULL)  w->data->contenttype = CT_IMAGE_SVG_XML;
-       else if(strstr(filename, ".ttf")  != NULL)  w->data->contenttype = CT_APPLICATION_X_FONT_TRUETYPE;
-       else if(strstr(filename, ".otf")  != NULL)  w->data->contenttype = CT_APPLICATION_X_FONT_OPENTYPE;
-       else if(strstr(filename, ".woff") != NULL)  w->data->contenttype = CT_APPLICATION_FONT_WOFF;
-       else if(strstr(filename, ".eot")  != NULL)  w->data->contenttype = CT_APPLICATION_VND_MS_FONTOBJ;
-       else w->data->contenttype = CT_APPLICATION_OCTET_STREAM;
+                if(strstr(filename, ".html") != NULL)  w->response.data->contenttype = CT_TEXT_HTML;
+       else if(strstr(filename, ".js")   != NULL)      w->response.data->contenttype = CT_APPLICATION_X_JAVASCRIPT;
+       else if(strstr(filename, ".css")  != NULL)      w->response.data->contenttype = CT_TEXT_CSS;
+       else if(strstr(filename, ".xml")  != NULL)      w->response.data->contenttype = CT_TEXT_XML;
+       else if(strstr(filename, ".xsl")  != NULL)      w->response.data->contenttype = CT_TEXT_XSL;
+       else if(strstr(filename, ".txt")  != NULL)  w->response.data->contenttype = CT_TEXT_PLAIN;
+       else if(strstr(filename, ".svg")  != NULL)  w->response.data->contenttype = CT_IMAGE_SVG_XML;
+       else if(strstr(filename, ".ttf")  != NULL)  w->response.data->contenttype = CT_APPLICATION_X_FONT_TRUETYPE;
+       else if(strstr(filename, ".otf")  != NULL)  w->response.data->contenttype = CT_APPLICATION_X_FONT_OPENTYPE;
+       else if(strstr(filename, ".woff2")!= NULL)  w->response.data->contenttype = CT_APPLICATION_FONT_WOFF2;
+       else if(strstr(filename, ".woff") != NULL)  w->response.data->contenttype = CT_APPLICATION_FONT_WOFF;
+       else if(strstr(filename, ".eot")  != NULL)  w->response.data->contenttype = CT_APPLICATION_VND_MS_FONTOBJ;
+       else if(strstr(filename, ".png")  != NULL)  w->response.data->contenttype = CT_IMAGE_PNG;
+       else if(strstr(filename, ".jpg")  != NULL)  w->response.data->contenttype = CT_IMAGE_JPG;
+       else if(strstr(filename, ".jpeg") != NULL)  w->response.data->contenttype = CT_IMAGE_JPG;
+       else if(strstr(filename, ".gif")  != NULL)  w->response.data->contenttype = CT_IMAGE_GIF;
+       else if(strstr(filename, ".bmp")  != NULL)  w->response.data->contenttype = CT_IMAGE_BMP;
+       else if(strstr(filename, ".ico")  != NULL)  w->response.data->contenttype = CT_IMAGE_XICON;
+       else if(strstr(filename, ".icns") != NULL)  w->response.data->contenttype = CT_IMAGE_ICNS;
+       else w->response.data->contenttype = CT_APPLICATION_OCTET_STREAM;
 
        debug(D_WEB_CLIENT_ACCESS, "%llu: Sending file '%s' (%ld bytes, ifd %d, ofd %d).", w->id, webfilename, stat.st_size, w->ifd, w->ofd);
 
        w->mode = WEB_CLIENT_MODE_FILECOPY;
        w->wait_receive = 1;
        w->wait_send = 0;
-       w->data->bytes = 0;
-       w->data->buffer[0] = '\0';
-       w->data->rbytes = stat.st_size;
-       w->data->date = stat.st_mtim.tv_sec;
+       buffer_flush(w->response.data);
+       w->response.rlen = stat.st_size;
+       w->response.data->date = stat.st_mtim.tv_sec;
 
        return 200;
 }
 
-void web_client_reset(struct web_client *w)
+
+#ifdef NETDATA_WITH_ZLIB
+void web_client_enable_deflate(struct web_client *w) {
+       if(w->response.zinitialized == 1) {
+               error("%llu: Compression has already be initialized for this client.", w->id);
+               return;
+       }
+
+       if(w->response.sent) {
+               error("%llu: Cannot enable compression in the middle of a conversation.", w->id);
+               return;
+       }
+
+       w->response.zstream.zalloc = Z_NULL;
+       w->response.zstream.zfree = Z_NULL;
+       w->response.zstream.opaque = Z_NULL;
+
+       w->response.zstream.next_in = (Bytef *)w->response.data->buffer;
+       w->response.zstream.avail_in = 0;
+       w->response.zstream.total_in = 0;
+
+       w->response.zstream.next_out = w->response.zbuffer;
+       w->response.zstream.avail_out = 0;
+       w->response.zstream.total_out = 0;
+
+       w->response.zstream.zalloc = Z_NULL;
+       w->response.zstream.zfree = Z_NULL;
+       w->response.zstream.opaque = Z_NULL;
+
+//     if(deflateInit(&w->response.zstream, Z_DEFAULT_COMPRESSION) != Z_OK) {
+//             error("%llu: Failed to initialize zlib. Proceeding without compression.", w->id);
+//             return;
+//     }
+
+       // Select GZIP compression: windowbits = 15 + 16 = 31
+       if(deflateInit2(&w->response.zstream, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 31, 8, Z_DEFAULT_STRATEGY) != Z_OK) {
+               error("%llu: Failed to initialize zlib. Proceeding without compression.", w->id);
+               return;
+       }
+
+       w->response.zsent = 0;
+       w->response.zoutput = 1;
+       w->response.zinitialized = 1;
+
+       debug(D_DEFLATE, "%llu: Initialized compression.", w->id);
+}
+#endif // NETDATA_WITH_ZLIB
+
+uint32_t web_client_api_request_v1_data_options(char *o)
 {
-       struct timeval tv;
-       gettimeofday(&tv, NULL);
+       uint32_t ret = 0x00000000;
+       char *tok;
+
+       while(o && *o && (tok = mystrsep(&o, ", |"))) {
+               if(!*tok) continue;
+
+               if(!strcmp(tok, "nonzero"))
+                       ret |= RRDR_OPTION_NONZERO;
+               else if(!strcmp(tok, "flip") || !strcmp(tok, "reversed") || !strcmp(tok, "reverse"))
+                       ret |= RRDR_OPTION_REVERSED;
+               else if(!strcmp(tok, "jsonwrap"))
+                       ret |= RRDR_OPTION_JSON_WRAP;
+               else if(!strcmp(tok, "min2max"))
+                       ret |= RRDR_OPTION_MIN2MAX;
+               else if(!strcmp(tok, "ms") || !strcmp(tok, "milliseconds"))
+                       ret |= RRDR_OPTION_MILLISECONDS;
+               else if(!strcmp(tok, "abs") || !strcmp(tok, "absolute") || !strcmp(tok, "absolute_sum") || !strcmp(tok, "absolute-sum"))
+                       ret |= RRDR_OPTION_ABSOLUTE;
+               else if(!strcmp(tok, "seconds"))
+                       ret |= RRDR_OPTION_SECONDS;
+               else if(!strcmp(tok, "null2zero"))
+                       ret |= RRDR_OPTION_NULL2ZERO;
+               else if(!strcmp(tok, "objectrows"))
+                       ret |= RRDR_OPTION_OBJECTSROWS;
+               else if(!strcmp(tok, "google_json"))
+                       ret |= RRDR_OPTION_GOOGLE_JSON;
+               else if(!strcmp(tok, "percentage"))
+                       ret |= RRDR_OPTION_PERCENTAGE;
+       }
 
-       long sent = (w->mode == WEB_CLIENT_MODE_FILECOPY)?w->data->rbytes:w->data->bytes;
+       return ret;
+}
 
-#ifndef NETDATA_WITHOUT_ZLIB
-       if(likely(w->zoutput)) sent = (long)w->zstream.total_out;
-#endif
+uint32_t web_client_api_request_v1_data_format(char *name)
+{
+       if(!strcmp(name, DATASOURCE_FORMAT_DATATABLE_JSON)) // datatable
+               return DATASOURCE_DATATABLE_JSON;
 
-       long size = (w->mode == WEB_CLIENT_MODE_FILECOPY)?w->data->rbytes:w->data->bytes;
+       else if(!strcmp(name, DATASOURCE_FORMAT_DATATABLE_JSONP)) // datasource
+               return DATASOURCE_DATATABLE_JSONP;
 
-       if(likely(w->last_url[0]))
-               log_access("%llu: (sent/all = %ld/%ld bytes %0.0f%%, prep/sent/total = %0.2f/%0.2f/%0.2f ms) %s: '%s'",
-                       w->id,
-                       sent, size, -((size>0)?((float)(size-sent)/(float)size * 100.0):0.0),
-                       (float)usecdiff(&w->tv_ready, &w->tv_in) / 1000.0,
-                       (float)usecdiff(&tv, &w->tv_ready) / 1000.0,
-                       (float)usecdiff(&tv, &w->tv_in) / 1000.0,
-                       (w->mode == WEB_CLIENT_MODE_FILECOPY)?"filecopy":"data",
-                                       w->last_url
-               );
+       else if(!strcmp(name, DATASOURCE_FORMAT_JSON)) // json
+               return DATASOURCE_JSON;
 
-       debug(D_WEB_CLIENT, "%llu: Reseting client.", w->id);
+       else if(!strcmp(name, DATASOURCE_FORMAT_JSONP)) // jsonp
+               return DATASOURCE_JSONP;
 
-       if(unlikely(w->mode == WEB_CLIENT_MODE_FILECOPY)) {
-               debug(D_WEB_CLIENT, "%llu: Closing filecopy input file.", w->id);
-               close(w->ifd);
-               w->ifd = w->ofd;
+       else if(!strcmp(name, DATASOURCE_FORMAT_SSV)) // ssv
+               return DATASOURCE_SSV;
+
+       else if(!strcmp(name, DATASOURCE_FORMAT_CSV)) // csv
+               return DATASOURCE_CSV;
+
+       else if(!strcmp(name, DATASOURCE_FORMAT_TSV) || !strcmp(name, "tsv-excel")) // tsv
+               return DATASOURCE_TSV;
+
+       else if(!strcmp(name, DATASOURCE_FORMAT_HTML)) // html
+               return DATASOURCE_HTML;
+
+       else if(!strcmp(name, DATASOURCE_FORMAT_JS_ARRAY)) // array
+               return DATASOURCE_JS_ARRAY;
+
+       else if(!strcmp(name, DATASOURCE_FORMAT_SSV_COMMA)) // ssvcomma
+               return DATASOURCE_SSV_COMMA;
+
+       else if(!strcmp(name, DATASOURCE_FORMAT_CSV_JSON_ARRAY)) // csvjsonarray
+               return DATASOURCE_CSV_JSON_ARRAY;
+
+       return DATASOURCE_JSON;
+}
+
+uint32_t web_client_api_request_v1_data_google_format(char *name)
+{
+       if(!strcmp(name, "json"))
+               return DATASOURCE_DATATABLE_JSONP;
+
+       else if(!strcmp(name, "html"))
+               return DATASOURCE_HTML;
+
+       else if(!strcmp(name, "csv"))
+               return DATASOURCE_CSV;
+
+       else if(!strcmp(name, "tsv-excel"))
+               return DATASOURCE_TSV;
+
+       return DATASOURCE_JSON;
+}
+
+int web_client_api_request_v1_data_group(char *name)
+{
+       if(!strcmp(name, "max"))
+               return GROUP_MAX;
+
+       else if(!strcmp(name, "average"))
+               return GROUP_AVERAGE;
+
+       return GROUP_MAX;
+}
+
+int web_client_api_request_v1_charts(struct web_client *w, char *url)
+{
+       if(url) { ; }
+
+       buffer_flush(w->response.data);
+       w->response.data->contenttype = CT_APPLICATION_JSON;
+       rrd_stats_api_v1_charts(w->response.data);
+       return 200;
+}
+
+int web_client_api_request_v1_chart(struct web_client *w, char *url)
+{
+       int ret = 400;
+       char *chart = NULL;
+
+       buffer_flush(w->response.data);
+
+       while(url) {
+               char *value = mystrsep(&url, "?&[]");
+               if(!value || !*value) continue;
+
+               char *name = mystrsep(&value, "=");
+               if(!name || !*name) continue;
+               if(!value || !*value) continue;
+
+               // name and value are now the parameters
+               // they are not null and not empty
+
+               if(!strcmp(name, "chart")) chart = value;
+               //else {
+               ///     buffer_sprintf(w->response.data, "Unknown parameter '%s' in request.", name);
+               //      goto cleanup;
+               //}
        }
 
-       w->last_url[0] = '\0';
+       if(!chart || !*chart) {
+               buffer_sprintf(w->response.data, "No chart id is given at the request.");
+               goto cleanup;
+       }
 
-       w->data->contenttype = CT_TEXT_PLAIN;
-       w->mode = WEB_CLIENT_MODE_NORMAL;
+       RRDSET *st = rrdset_find(chart);
+       if(!st) st = rrdset_find_byname(chart);
+       if(!st) {
+               buffer_sprintf(w->response.data, "Chart '%s' is not found.", chart);
+               ret = 404;
+               goto cleanup;
+       }
 
-       w->data->rbytes = 0;
-       w->data->bytes = 0;
-       w->data->sent = 0;
+       w->response.data->contenttype = CT_APPLICATION_JSON;
+       rrd_stats_api_v1_chart(st, w->response.data);
+       return 200;
 
-       w->response_header[0] = '\0';
-       w->data->buffer[0] = '\0';
+cleanup:
+       return ret;
+}
 
-       w->wait_receive = 1;
-       w->wait_send = 0;
+// returns the HTTP code
+int web_client_api_request_v1_data(struct web_client *w, char *url)
+{
+       debug(D_WEB_CLIENT, "%llu: API v1 data with URL '%s'", w->id, url);
 
-       w->zoutput = 0;
+       int ret = 400;
+       BUFFER *dimensions = NULL;
 
-       // if we had enabled compression, release it
-#ifndef NETDATA_WITHOUT_ZLIB
-       if(w->zinitialized) {
-               debug(D_DEFLATE, "%llu: Reseting compression.", w->id);
-               deflateEnd(&w->zstream);
-               w->zsent = 0;
-               w->zhave = 0;
-               w->zstream.avail_in = 0;
-               w->zstream.avail_out = 0;
-               w->zstream.total_in = 0;
-               w->zstream.total_out = 0;
-               w->zinitialized = 0;
-       }
-#endif // NETDATA_WITHOUT_ZLIB
+       buffer_flush(w->response.data);
+
+       char    *google_version = "0.6",
+                       *google_reqId = "0",
+                       *google_sig = "0",
+                       *google_out = "json",
+                       *responseHandler = NULL,
+                       *outFileName = NULL;
+
+       time_t last_timestamp_in_data = 0, google_timestamp = 0;
+
+       char *chart = NULL
+                       , *before_str = NULL
+                       , *after_str = NULL
+                       , *points_str = NULL;
+
+       int group = GROUP_MAX;
+       uint32_t format = DATASOURCE_JSON;
+       uint32_t options = 0x00000000;
+
+       while(url) {
+               char *value = mystrsep(&url, "?&[]");
+               if(!value || !*value) continue;
+
+               char *name = mystrsep(&value, "=");
+               if(!name || !*name) continue;
+               if(!value || !*value) continue;
+
+               debug(D_WEB_CLIENT, "%llu: API v1 data query param '%s' with value '%s'", w->id, name, value);
+
+               // name and value are now the parameters
+               // they are not null and not empty
+
+               if(!strcmp(name, "chart")) chart = value;
+               else if(!strcmp(name, "dimension") || !strcmp(name, "dim") || !strcmp(name, "dimensions") || !strcmp(name, "dims")) {
+                       if(!dimensions) dimensions = buffer_create(strlen(value));
+                       if(dimensions) {
+                               buffer_strcat(dimensions, "|");
+                               buffer_strcat(dimensions, value);
+                       }
+               }
+               else if(!strcmp(name, "after")) after_str = value;
+               else if(!strcmp(name, "before")) before_str = value;
+               else if(!strcmp(name, "points")) points_str = value;
+               else if(!strcmp(name, "group")) {
+                       group = web_client_api_request_v1_data_group(value);
+               }
+               else if(!strcmp(name, "format")) {
+                       format = web_client_api_request_v1_data_format(value);
+               }
+               else if(!strcmp(name, "options")) {
+                       options |= web_client_api_request_v1_data_options(value);
+               }
+               else if(!strcmp(name, "callback")) {
+                       responseHandler = value;
+               }
+               else if(!strcmp(name, "filename")) {
+                       outFileName = value;
+               }
+               else if(!strcmp(name, "tqx")) {
+                       // parse Google Visualization API options
+                       // https://developers.google.com/chart/interactive/docs/dev/implementing_data_source
+                       char *tqx_name, *tqx_value;
+
+                       while(value) {
+                               tqx_value = mystrsep(&value, ";");
+                               if(!tqx_value || !*tqx_value) continue;
+
+                               tqx_name = mystrsep(&tqx_value, ":");
+                               if(!tqx_name || !*tqx_name) continue;
+                               if(!tqx_value || !*tqx_value) continue;
+
+                               if(!strcmp(tqx_name, "version"))
+                                       google_version = tqx_value;
+                               else if(!strcmp(tqx_name, "reqId"))
+                                       google_reqId = tqx_value;
+                               else if(!strcmp(tqx_name, "sig")) {
+                                       google_sig = tqx_value;
+                                       google_timestamp = strtoul(google_sig, NULL, 0);
+                               }
+                               else if(!strcmp(tqx_name, "out")) {
+                                       google_out = tqx_value;
+                                       format = web_client_api_request_v1_data_google_format(google_out);
+                               }
+                               else if(!strcmp(tqx_name, "responseHandler"))
+                                       responseHandler = tqx_value;
+                               else if(!strcmp(tqx_name, "outFileName"))
+                                       outFileName = tqx_value;
+                       }
+               }
+       }
+
+       if(!chart || !*chart) {
+               buffer_sprintf(w->response.data, "No chart id is given at the request.");
+               goto cleanup;
+       }
+
+       RRDSET *st = rrdset_find(chart);
+       if(!st) st = rrdset_find_byname(chart);
+       if(!st) {
+               buffer_sprintf(w->response.data, "Chart '%s' is not found.", chart);
+               ret = 404;
+               goto cleanup;
+       }
+
+       long long before = (before_str && *before_str)?atol(before_str):0;
+       long long after  = (after_str  && *after_str) ?atol(after_str):0;
+       int       points = (points_str && *points_str)?atoi(points_str):0;
+
+       debug(D_WEB_CLIENT, "%llu: API command 'data' for chart '%s', dimensions '%s', after '%lld', before '%lld', points '%d', group '%u', format '%u', options '0x%08x'"
+                       , w->id
+                       , chart
+                       , (dimensions)?buffer_tostring(dimensions):""
+                       , after
+                       , before
+                       , points
+                       , group
+                       , format
+                       , options
+                       );
+
+       if(outFileName && *outFileName) {
+               buffer_sprintf(w->response.header, "Content-Disposition: attachment; filename=\"%s\"\r\n", outFileName);
+               error("generating outfilename header: '%s'", outFileName);
+       }
+
+       if(format == DATASOURCE_DATATABLE_JSONP) {
+               if(responseHandler == NULL)
+                       responseHandler = "google.visualization.Query.setResponse";
+
+               debug(D_WEB_CLIENT_ACCESS, "%llu: GOOGLE JSON/JSONP: version = '%s', reqId = '%s', sig = '%s', out = '%s', responseHandler = '%s', outFileName = '%s'",
+                               w->id, google_version, google_reqId, google_sig, google_out, responseHandler, outFileName
+                       );
+
+               buffer_sprintf(w->response.data,
+                       "%s({version:'%s',reqId:'%s',status:'ok',sig:'%lu',table:",
+                       responseHandler, google_version, google_reqId, st->last_updated.tv_sec);
+       }
+       else if(format == DATASOURCE_JSONP) {
+               if(responseHandler == NULL)
+                       responseHandler = "callback";
+
+               buffer_strcat(w->response.data, responseHandler);
+               buffer_strcat(w->response.data, "(");
+       }
+
+       ret = rrd2format(st, w->response.data, dimensions, format, points, after, before, group, options, &last_timestamp_in_data);
+
+       if(format == DATASOURCE_DATATABLE_JSONP) {
+               if(google_timestamp < last_timestamp_in_data)
+                       buffer_strcat(w->response.data, "});");
+
+               else {
+                       // the client already has the latest data
+                       buffer_flush(w->response.data);
+                       buffer_sprintf(w->response.data,
+                               "%s({version:'%s',reqId:'%s',status:'error',errors:[{reason:'not_modified',message:'Data not modified'}]});",
+                               responseHandler, google_version, google_reqId);
+               }
+       }
+       else if(format == DATASOURCE_JSONP)
+               buffer_strcat(w->response.data, ");");
+
+cleanup:
+       if(dimensions) buffer_free(dimensions);
+       return ret;
 }
 
-#ifndef NETDATA_WITHOUT_ZLIB
-void web_client_enable_deflate(struct web_client *w) {
-       if(w->zinitialized == 1) {
-               error("%llu: Compression has already be initialized for this client.", w->id);
-               return;
+int web_client_api_request_v1_registry(struct web_client *w, char *url)
+{
+       char person_guid[36 + 1] = "";
+
+       debug(D_WEB_CLIENT, "%llu: API v1 registry with URL '%s'", w->id, url);
+
+       char *cookie = strstr(w->response.data->buffer, " " NETDATA_REGISTRY_COOKIE_NAME "=");
+       if(cookie) {
+               strncpy(person_guid, &cookie[sizeof(NETDATA_REGISTRY_COOKIE_NAME) + 1], 36);
+               person_guid[36] = '\0';
        }
 
-       if(w->data->sent) {
-               error("%llu: Cannot enable compression in the middle of a conversation.", w->id);
-               return;
+       char action = '\0';
+       char *machine_guid = NULL,
+                       *machine_url = NULL,
+                       *url_name = NULL,
+                       *search_machine_guid = NULL,
+                       *delete_url = NULL;
+
+       while(url) {
+               char *value = mystrsep(&url, "?&[]");
+               if (!value || !*value) continue;
+
+               char *name = mystrsep(&value, "=");
+               if (!name || !*name) continue;
+               if (!value || !*value) continue;
+
+               debug(D_WEB_CLIENT, "%llu: API v1 registry query param '%s' with value '%s'", w->id, name, value);
+
+               if(!strcmp(name, "action")) {
+                       if(!strcmp(value, "access")) action = 'A';
+                       else if(!strcmp(value, "delete")) action = 'D';
+                       else if(!strcmp(value, "search")) action = 'S';
+               }
+               else if(!strcmp(name, "machine"))
+                       machine_guid = value;
+
+               else if(!strcmp(name, "url"))
+                       machine_url = value;
+
+               else if(action == 'A') {
+                       if(!strcmp(name, "name"))
+                               url_name = value;
+               }
+               else if(action == 'D') {
+                       if(!strcmp(name, "delete_url"))
+                               delete_url = value;
+               }
+               else if(action == 'S') {
+                       if(!strcmp(name, "for"))
+                               search_machine_guid = value;
+               }
+       }
+
+       if((!action || !machine_guid || !machine_url) || (action == 'A' && !url_name) || (action == 'D' && !delete_url) || (action == 'S' && !search_machine_guid)) {
+               buffer_flush(w->response.data);
+               buffer_sprintf(w->response.data, "Invalid registry request - required parameters missing.");
+               return 400;
        }
 
-       w->zstream.zalloc = Z_NULL;
-       w->zstream.zfree = Z_NULL;
-       w->zstream.opaque = Z_NULL;
+       switch(action) {
+               case 'A':
+                       return registry_request_access_json(w, person_guid, machine_guid, machine_url, url_name, time(NULL));
 
-       w->zstream.next_in = (Bytef *)w->data->buffer;
-       w->zstream.avail_in = 0;
-       w->zstream.total_in = 0;
+               case 'D':
+                       return registry_request_delete_json(w, person_guid, machine_guid, machine_url, delete_url, time(NULL));
 
-       w->zstream.next_out = w->zbuffer;
-       w->zstream.avail_out = 0;
-       w->zstream.total_out = 0;
+               case 'S':
+                       return registry_request_search_json(w, person_guid, machine_guid, machine_url, search_machine_guid, time(NULL));
+       }
 
-       w->zstream.zalloc = Z_NULL;
-       w->zstream.zfree = Z_NULL;
-       w->zstream.opaque = Z_NULL;
+       buffer_flush(w->response.data);
+       buffer_sprintf(w->response.data, "Invalid or no registry action.");
+       return 400;
+}
 
-//     if(deflateInit(&w->zstream, Z_DEFAULT_COMPRESSION) != Z_OK) {
-//             error("%llu: Failed to initialize zlib. Proceeding without compression.", w->id);
-//             return;
-//     }
+int web_client_api_request_v1(struct web_client *w, char *url)
+{
+       static uint32_t data_hash = 0, chart_hash = 0, charts_hash = 0, registry_hash = 0;
 
-       // Select GZIP compression: windowbits = 15 + 16 = 31
-       if(deflateInit2(&w->zstream, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 31, 8, Z_DEFAULT_STRATEGY) != Z_OK) {
-               error("%llu: Failed to initialize zlib. Proceeding without compression.", w->id);
-               return;
+       if(unlikely(data_hash == 0)) {
+               data_hash = simple_hash("data");
+               chart_hash = simple_hash("chart");
+               charts_hash = simple_hash("charts");
+               registry_hash = simple_hash("registry");
        }
 
-       w->zsent = 0;
-       w->zoutput = 1;
-       w->zinitialized = 1;
+       // get the command
+       char *tok = mystrsep(&url, "/?&");
+       if(tok && *tok) {
+               debug(D_WEB_CLIENT, "%llu: Searching for API v1 command '%s'.", w->id, tok);
+               uint32_t hash = simple_hash(tok);
 
-       debug(D_DEFLATE, "%llu: Initialized compression.", w->id);
+               if(hash == data_hash && !strcmp(tok, "data"))
+                       return web_client_api_request_v1_data(w, url);
+
+               else if(hash == chart_hash && !strcmp(tok, "chart"))
+                       return web_client_api_request_v1_chart(w, url);
+
+               else if(hash == charts_hash && !strcmp(tok, "charts"))
+                       return web_client_api_request_v1_charts(w, url);
+
+               else if(hash == registry_hash && !strcmp(tok, "registry"))
+                       return web_client_api_request_v1_registry(w, url);
+
+               else {
+                       buffer_flush(w->response.data);
+                       buffer_sprintf(w->response.data, "Unsupported v1 API command: %s", tok);
+                       return 404;
+               }
+       }
+       else {
+               buffer_flush(w->response.data);
+               buffer_sprintf(w->response.data, "API v1 command?");
+               return 400;
+       }
+}
+
+int web_client_api_request(struct web_client *w, char *url)
+{
+       // get the api version
+       char *tok = mystrsep(&url, "/?&");
+       if(tok && *tok) {
+               debug(D_WEB_CLIENT, "%llu: Searching for API version '%s'.", w->id, tok);
+               if(strcmp(tok, "v1") == 0)
+                       return web_client_api_request_v1(w, url);
+               else {
+                       buffer_flush(w->response.data);
+                       buffer_sprintf(w->response.data, "Unsupported API version: %s", tok);
+                       return 404;
+               }
+       }
+       else {
+               buffer_flush(w->response.data);
+               buffer_sprintf(w->response.data, "Which API version?");
+               return 400;
+       }
 }
-#endif // NETDATA_WITHOUT_ZLIB
 
 int web_client_data_request(struct web_client *w, char *url, int datasource_type)
 {
+       RRDSET *st = NULL;
+
        char *args = strchr(url, '?');
        if(args) {
                *args='\0';
@@ -342,15 +937,18 @@ int web_client_data_request(struct web_client *w, char *url, int datasource_type
 
        // get the name of the data to show
        char *tok = mystrsep(&url, "/");
-       debug(D_WEB_CLIENT, "%llu: Searching for RRD data with name '%s'.", w->id, tok);
 
        // do we have such a data set?
-       RRDSET *st = rrdset_find_byname(tok);
-       if(!st) st = rrdset_find(tok);
+       if(tok && *tok) {
+               debug(D_WEB_CLIENT, "%llu: Searching for RRD data with name '%s'.", w->id, tok);
+               st = rrdset_find_byname(tok);
+               if(!st) st = rrdset_find(tok);
+       }
+
        if(!st) {
                // we don't have it
                // try to send a file with that name
-               w->data->bytes = 0;
+               buffer_flush(w->response.data);
                return(mysendfile(w, tok));
        }
 
@@ -373,38 +971,40 @@ int web_client_data_request(struct web_client *w, char *url, int datasource_type
        if(url) {
                // parse the group count required
                tok = mystrsep(&url, "/");
-               if(tok) group_count = atoi(tok);
+               if(tok && *tok) group_count = atoi(tok);
                if(group_count < 1) group_count = 1;
                //if(group_count > save_history / 20) group_count = save_history / 20;
        }
        if(url) {
                // parse the grouping method required
                tok = mystrsep(&url, "/");
-               if(strcmp(tok, "max") == 0) group_method = GROUP_MAX;
-               else if(strcmp(tok, "average") == 0) group_method = GROUP_AVERAGE;
-               else if(strcmp(tok, "sum") == 0) group_method = GROUP_SUM;
-               else debug(D_WEB_CLIENT, "%llu: Unknown group method '%s'", w->id, tok);
+               if(tok && *tok) {
+                       if(strcmp(tok, "max") == 0) group_method = GROUP_MAX;
+                       else if(strcmp(tok, "average") == 0) group_method = GROUP_AVERAGE;
+                       else if(strcmp(tok, "sum") == 0) group_method = GROUP_SUM;
+                       else debug(D_WEB_CLIENT, "%llu: Unknown group method '%s'", w->id, tok);
+               }
        }
        if(url) {
                // parse after time
                tok = mystrsep(&url, "/");
-               if(tok) after = strtoul(tok, NULL, 10);
+               if(tok && *tok) after = strtoul(tok, NULL, 10);
                if(after < 0) after = 0;
        }
        if(url) {
                // parse before time
                tok = mystrsep(&url, "/");
-               if(tok) before = strtoul(tok, NULL, 10);
+               if(tok && *tok) before = strtoul(tok, NULL, 10);
                if(before < 0) before = 0;
        }
        if(url) {
                // parse nonzero
                tok = mystrsep(&url, "/");
-               if(tok && strcmp(tok, "nonzero") == 0) nonzero = 1;
+               if(tok && *tok && strcmp(tok, "nonzero") == 0) nonzero = 1;
        }
 
-       w->data->contenttype = CT_APPLICATION_JSON;
-       w->data->bytes = 0;
+       w->response.data->contenttype = CT_APPLICATION_JSON;
+       buffer_flush(w->response.data);
 
        char *google_version = "0.6";
        char *google_reqId = "0";
@@ -412,16 +1012,16 @@ int web_client_data_request(struct web_client *w, char *url, int datasource_type
        char *google_out = "json";
        char *google_responseHandler = "google.visualization.Query.setResponse";
        char *google_outFileName = NULL;
-       unsigned long last_timestamp_in_data = 0;
-       if(datasource_type == DATASOURCE_GOOGLE_JSON || datasource_type == DATASOURCE_GOOGLE_JSONP) {
+       time_t last_timestamp_in_data = 0;
+       if(datasource_type == DATASOURCE_DATATABLE_JSON || datasource_type == DATASOURCE_DATATABLE_JSONP) {
 
-               w->data->contenttype = CT_APPLICATION_X_JAVASCRIPT;
+               w->response.data->contenttype = CT_APPLICATION_X_JAVASCRIPT;
 
                while(args) {
                        tok = mystrsep(&args, "&");
-                       if(tok) {
+                       if(tok && *tok) {
                                char *name = mystrsep(&tok, "=");
-                               if(name && strcmp(name, "tqx") == 0) {
+                               if(name && *name && strcmp(name, "tqx") == 0) {
                                        char *key = mystrsep(&tok, ":");
                                        char *value = mystrsep(&tok, ";");
                                        if(key && value && *key && *value) {
@@ -451,12 +1051,12 @@ int web_client_data_request(struct web_client *w, char *url, int datasource_type
                        w->id, google_version, google_reqId, google_sig, google_out, google_responseHandler, google_outFileName
                        );
 
-               if(datasource_type == DATASOURCE_GOOGLE_JSONP) {
+               if(datasource_type == DATASOURCE_DATATABLE_JSONP) {
                        last_timestamp_in_data = strtoul(google_sig, NULL, 0);
 
                        // check the client wants json
                        if(strcmp(google_out, "json") != 0) {
-                               w->data->bytes = snprintf(w->data->buffer, w->data->size,
+                               buffer_sprintf(w->response.data,
                                        "%s({version:'%s',reqId:'%s',status:'error',errors:[{reason:'invalid_query',message:'output format is not supported',detailed_message:'the format %s requested is not supported by netdata.'}]});",
                                        google_responseHandler, google_version, google_reqId, google_out);
                                        return 200;
@@ -464,22 +1064,23 @@ int web_client_data_request(struct web_client *w, char *url, int datasource_type
                }
        }
 
-       if(datasource_type == DATASOURCE_GOOGLE_JSONP) {
-               w->data->bytes = snprintf(w->data->buffer, w->data->size,
+       if(datasource_type == DATASOURCE_DATATABLE_JSONP) {
+               buffer_sprintf(w->response.data,
                        "%s({version:'%s',reqId:'%s',status:'ok',sig:'%lu',table:",
                        google_responseHandler, google_version, google_reqId, st->last_updated.tv_sec);
        }
 
        debug(D_WEB_CLIENT_ACCESS, "%llu: Sending RRD data '%s' (id %s, %d lines, %d group, %d group_method, %lu after, %lu before).", w->id, st->name, st->id, lines, group_count, group_method, after, before);
-       unsigned long timestamp_in_data = rrd_stats_json(datasource_type, st, w->data, lines, group_count, group_method, after, before, nonzero);
+       time_t timestamp_in_data = rrd_stats_json(datasource_type, st, w->response.data, lines, group_count, group_method, after, before, nonzero);
 
-       if(datasource_type == DATASOURCE_GOOGLE_JSONP) {
+       if(datasource_type == DATASOURCE_DATATABLE_JSONP) {
                if(timestamp_in_data > last_timestamp_in_data)
-                       w->data->bytes += snprintf(&w->data->buffer[w->data->bytes], w->data->size - w->data->bytes, "});");
+                       buffer_strcat(w->response.data, "});");
 
                else {
                        // the client already has the latest data
-                       w->data->bytes = snprintf(w->data->buffer, w->data->size,
+                       buffer_flush(w->response.data);
+                       buffer_sprintf(w->response.data,
                                "%s({version:'%s',reqId:'%s',status:'error',errors:[{reason:'not_modified',message:'Data not modified'}]});",
                                google_responseHandler, google_version, google_reqId);
                }
@@ -500,9 +1101,9 @@ int web_client_parse_request(struct web_client *w) {
 
        web_client_clean_request(w);
 
-       debug(D_WEB_DATA, "%llu: Processing data buffer of %d bytes: '%s'.", w->id, w->data->bytes, w->data->buffer);
+       debug(D_WEB_DATA, "%llu: Processing data buffer of %d bytes: '%s'.", w->id, w->response.data->bytes, w->response.data->buffer);
 
-       char *buf = w->data->buffer;
+       char *buf = w->response.data->buffer;
        char *line, *tok;
 
        // ------------------------------------------------------------------------
@@ -536,201 +1137,273 @@ cleanup:
 }
 */
 
+// get the request buffer, just after the GET or OPTIONS
+// and find the url to be decoded, decode it and return
+// a newly allocated buffer with it
+static inline char *find_url_and_decode_it(char *request) {
+       char *e = request, *url = NULL;
+
+       // find the SPACE + "HTTP/"
+       while(*e) {
+               // find the space
+               while (*e && *e != ' ') e++;
+
+               // is it SPACE + "HTTP/" ?
+               if(*e && !strncmp(e, " HTTP/", 6))
+                       break;
+       }
+
+       if(*e) {
+               // we have the end
+               *e = '\0';
+               url = url_decode(request);
+               *e = ' ';
+       }
+
+       return url;
+}
+
 void web_client_process(struct web_client *w) {
        int code = 500;
-       int bytes;
+       ssize_t bytes;
+       int enable_gzip = 0;
 
        w->wait_receive = 0;
 
        // check if we have an empty line (end of HTTP header)
-       if(strstr(w->data->buffer, "\r\n\r\n")) {
+       if(strstr(w->response.data->buffer, "\r\n\r\n")) {
                global_statistics_lock();
                global_statistics.web_requests++;
                global_statistics_unlock();
 
                gettimeofday(&w->tv_in, NULL);
-               debug(D_WEB_DATA, "%llu: Processing data buffer of %d bytes: '%s'.", w->id, w->data->bytes, w->data->buffer);
+               debug(D_WEB_DATA, "%llu: Processing data buffer of %d bytes: '%s'.", w->id, w->response.data->len, w->response.data->buffer);
 
                // check if the client requested keep-alive HTTP
-               if(strcasestr(w->data->buffer, "Connection: keep-alive")) w->keepalive = 1;
+               if(strcasestr(w->response.data->buffer, "Connection: keep-alive")) w->keepalive = 1;
                else w->keepalive = 0;
 
-#ifndef NETDATA_WITHOUT_ZLIB
+#ifdef NETDATA_WITH_ZLIB
                // check if the client accepts deflate
-               if(web_enable_gzip && strstr(w->data->buffer, "gzip"))
-                       web_client_enable_deflate(w);
-#endif // NETDATA_WITHOUT_ZLIB
+               if(web_enable_gzip && strstr(w->response.data->buffer, "gzip"))
+                       enable_gzip = 1;
+#endif // NETDATA_WITH_ZLIB
 
-               int datasource_type = DATASOURCE_GOOGLE_JSONP;
-               //if(strstr(w->data->buffer, "X-DataSource-Auth"))
-               //      datasource_type = DATASOURCE_GOOGLE_JSON;
+               w->mode = WEB_CLIENT_MODE_NORMAL;
 
-               char *buf = w->data->buffer;
-               char *tok = strsep(&buf, " \r\n");
-               char *url = NULL;
+               char *tok = (char *)buffer_tostring(w->response.data);
+               char *url = NULL, *encoded_url = NULL;
                char *pointer_to_free = NULL; // keep url_decode() allocated buffer
 
-               if(buf && strcmp(tok, "GET") == 0) {
-                       tok = strsep(&buf, " \r\n");
-                       pointer_to_free = url = url_decode(tok);
-                       debug(D_WEB_CLIENT, "%llu: Processing HTTP GET on url '%s'.", w->id, url);
+               if(!strncmp(tok, "GET ", 4))
+                       encoded_url = &tok[4];
+               else if(!strncmp(tok, "OPTIONS ", 8)) {
+                       encoded_url = &tok[8];
+                       w->mode = WEB_CLIENT_MODE_OPTIONS;
                }
-               else if (buf && strcmp(tok, "POST") == 0) {
-                       w->keepalive = 0;
-                       tok = strsep(&buf, " \r\n");
-                       pointer_to_free = url = url_decode(tok);
 
-                       debug(D_WEB_CLIENT, "%llu: I don't know how to handle POST with form data. Assuming it is a GET on url '%s'.", w->id, url);
+               if(encoded_url) {
+                       pointer_to_free = url = find_url_and_decode_it(encoded_url);
+
+                       if(url) debug(D_WEB_CLIENT, "%llu: Processing url '%s'.", w->id, url);
+                       else debug(D_WEB_CLIENT, "%llu: Cannot find a valid URL in '%s'", w->id, encoded_url);
                }
 
                w->last_url[0] = '\0';
-               if(url) {
+
+               if(w->mode == WEB_CLIENT_MODE_OPTIONS) {
                        strncpy(w->last_url, url, URL_MAX);
                        w->last_url[URL_MAX] = '\0';
 
-                       tok = mystrsep(&url, "/?&");
+                       code = 200;
+                       w->response.data->contenttype = CT_TEXT_PLAIN;
+                       buffer_flush(w->response.data);
+                       buffer_strcat(w->response.data, "OK");
+               }
+               else if(url) {
+#ifdef NETDATA_WITH_ZLIB
+                       if(enable_gzip)
+                               web_client_enable_deflate(w);
+#endif
 
-                       debug(D_WEB_CLIENT, "%llu: Processing command '%s'.", w->id, tok);
+                       strncpy(w->last_url, url, URL_MAX);
+                       w->last_url[URL_MAX] = '\0';
 
-                       if(strcmp(tok, WEB_PATH_DATA) == 0) { // "data"
-                               // the client is requesting rrd data
-                               datasource_type = DATASOURCE_JSON;
-                               code = web_client_data_request(w, url, datasource_type);
-                       }
-                       else if(strcmp(tok, WEB_PATH_DATASOURCE) == 0) { // "datasource"
-                               // the client is requesting google datasource
-                               code = web_client_data_request(w, url, datasource_type);
-                       }
-                       else if(strcmp(tok, WEB_PATH_GRAPH) == 0) { // "graph"
-                               // the client is requesting an rrd graph
-
-                               // get the name of the data to show
-                               tok = mystrsep(&url, "/?&");
-                               debug(D_WEB_CLIENT, "%llu: Searching for RRD data with name '%s'.", w->id, tok);
-
-                               // do we have such a data set?
-                               RRDSET *st = rrdset_find_byname(tok);
-                               if(!st) st = rrdset_find(tok);
-                               if(!st) {
-                                       // we don't have it
-                                       // try to send a file with that name
-                                       w->data->bytes = 0;
-                                       code = mysendfile(w, tok);
+                       tok = mystrsep(&url, "/?");
+                       if(tok && *tok) {
+                               debug(D_WEB_CLIENT, "%llu: Processing command '%s'.", w->id, tok);
+
+                               if(strcmp(tok, "api") == 0) {
+                                       // the client is requesting api access
+                                       code = web_client_api_request(w, url);
                                }
-                               else {
+#ifdef NETDATA_INTERNAL_CHECKS
+                               else if(strcmp(tok, "exit") == 0) {
                                        code = 200;
-                                       debug(D_WEB_CLIENT_ACCESS, "%llu: Sending %s.json of RRD_STATS...", w->id, st->name);
-                                       w->data->contenttype = CT_APPLICATION_JSON;
-                                       w->data->bytes = 0;
-                                       rrd_stats_graph_json(st, url, w->data);
+                                       w->response.data->contenttype = CT_TEXT_PLAIN;
+                                       buffer_flush(w->response.data);
+
+                                       if(!netdata_exit)
+                                               buffer_strcat(w->response.data, "ok, will do...");
+                                       else
+                                               buffer_strcat(w->response.data, "I am doing it already");
+
+                                       netdata_exit = 1;
                                }
-                       }
-                       else if(strcmp(tok, "debug") == 0) {
-                               w->data->bytes = 0;
-
-                               // get the name of the data to show
-                               tok = mystrsep(&url, "/?&");
-                               debug(D_WEB_CLIENT, "%llu: Searching for RRD data with name '%s'.", w->id, tok);
-
-                               // do we have such a data set?
-                               RRDSET *st = rrdset_find_byname(tok);
-                               if(!st) st = rrdset_find(tok);
-                               if(!st) {
-                                       code = 404;
-                                       web_buffer_printf(w->data, "Chart %s is not found.\r\n", tok);
-                                       debug(D_WEB_CLIENT_ACCESS, "%llu: %s is not found.", w->id, tok);
+#endif
+                               else if(strcmp(tok, WEB_PATH_DATA) == 0) { // "data"
+                                       // the client is requesting rrd data
+                                       code = web_client_data_request(w, url, DATASOURCE_JSON);
                                }
-                               else {
-                                       code = 200;
-                                       debug_flags |= D_RRD_STATS;
-                                       st->debug = st->debug?0:1;
-                                       web_buffer_printf(w->data, "Chart %s has now debug %s.\r\n", tok, st->debug?"enabled":"disabled");
-                                       debug(D_WEB_CLIENT_ACCESS, "%llu: debug for %s is %s.", w->id, tok, st->debug?"enabled":"disabled");
+                               else if(strcmp(tok, WEB_PATH_DATASOURCE) == 0) { // "datasource"
+                                       // the client is requesting google datasource
+                                       code = web_client_data_request(w, url, DATASOURCE_DATATABLE_JSONP);
                                }
-                       }
-                       else if(strcmp(tok, "mirror") == 0) {
-                               code = 200;
+                               else if(strcmp(tok, WEB_PATH_GRAPH) == 0) { // "graph"
+                                       // the client is requesting an rrd graph
+
+                                       // get the name of the data to show
+                                       tok = mystrsep(&url, "/?&");
+                                       if(tok && *tok) {
+                                               debug(D_WEB_CLIENT, "%llu: Searching for RRD data with name '%s'.", w->id, tok);
+
+                                               // do we have such a data set?
+                                               RRDSET *st = rrdset_find_byname(tok);
+                                               if(!st) st = rrdset_find(tok);
+                                               if(!st) {
+                                                       // we don't have it
+                                                       // try to send a file with that name
+                                                       buffer_flush(w->response.data);
+                                                       code = mysendfile(w, tok);
+                                               }
+                                               else {
+                                                       code = 200;
+                                                       debug(D_WEB_CLIENT_ACCESS, "%llu: Sending %s.json of RRD_STATS...", w->id, st->name);
+                                                       w->response.data->contenttype = CT_APPLICATION_JSON;
+                                                       buffer_flush(w->response.data);
+                                                       rrd_stats_graph_json(st, url, w->response.data);
+                                               }
+                                       }
+                                       else {
+                                               code = 400;
+                                               buffer_flush(w->response.data);
+                                               buffer_strcat(w->response.data, "Graph name?\r\n");
+                                       }
+                               }
+#ifdef NETDATA_INTERNAL_CHECKS
+                               else if(strcmp(tok, "debug") == 0) {
+                                       buffer_flush(w->response.data);
+
+                                       // get the name of the data to show
+                                       tok = mystrsep(&url, "/?&");
+                                       if(tok && *tok) {
+                                               debug(D_WEB_CLIENT, "%llu: Searching for RRD data with name '%s'.", w->id, tok);
+
+                                               // do we have such a data set?
+                                               RRDSET *st = rrdset_find_byname(tok);
+                                               if(!st) st = rrdset_find(tok);
+                                               if(!st) {
+                                                       code = 404;
+                                                       buffer_sprintf(w->response.data, "Chart %s is not found.\r\n", tok);
+                                                       debug(D_WEB_CLIENT_ACCESS, "%llu: %s is not found.", w->id, tok);
+                                               }
+                                               else {
+                                                       code = 200;
+                                                       debug_flags |= D_RRD_STATS;
+                                                       st->debug = st->debug?0:1;
+                                                       buffer_sprintf(w->response.data, "Chart %s has now debug %s.\r\n", tok, st->debug?"enabled":"disabled");
+                                                       debug(D_WEB_CLIENT_ACCESS, "%llu: debug for %s is %s.", w->id, tok, st->debug?"enabled":"disabled");
+                                               }
+                                       }
+                                       else {
+                                               code = 500;
+                                               buffer_flush(w->response.data);
+                                               buffer_strcat(w->response.data, "debug which chart?\r\n");
+                                       }
+                               }
+                               else if(strcmp(tok, "mirror") == 0) {
+                                       code = 200;
 
-                               debug(D_WEB_CLIENT_ACCESS, "%llu: Mirroring...", w->id);
+                                       debug(D_WEB_CLIENT_ACCESS, "%llu: Mirroring...", w->id);
 
-                               // replace the zero bytes with spaces
-                               int i;
-                               for(i = 0; i < w->data->size; i++)
-                                       if(w->data->buffer[i] == '\0') w->data->buffer[i] = ' ';
+                                       // replace the zero bytes with spaces
+                                       buffer_char_replace(w->response.data, '\0', ' ');
 
-                               // just leave the buffer as is
-                               // it will be copied back to the client
-                       }
-                       else if(strcmp(tok, "list") == 0) {
-                               code = 200;
+                                       // just leave the buffer as is
+                                       // it will be copied back to the client
+                               }
+#endif
+                               else if(strcmp(tok, "list") == 0) {
+                                       code = 200;
 
-                               debug(D_WEB_CLIENT_ACCESS, "%llu: Sending list of RRD_STATS...", w->id);
+                                       debug(D_WEB_CLIENT_ACCESS, "%llu: Sending list of RRD_STATS...", w->id);
 
-                               w->data->bytes = 0;
-                               RRDSET *st = rrdset_root;
+                                       buffer_flush(w->response.data);
+                                       RRDSET *st = rrdset_root;
 
-                               for ( ; st ; st = st->next )
-                                       web_buffer_printf(w->data, "%s\n", st->name);
-                       }
-                       else if(strcmp(tok, "all.json") == 0) {
-                               code = 200;
-                               debug(D_WEB_CLIENT_ACCESS, "%llu: Sending JSON list of all monitors of RRD_STATS...", w->id);
+                                       for ( ; st ; st = st->next )
+                                               buffer_sprintf(w->response.data, "%s\n", st->name);
+                               }
+                               else if(strcmp(tok, "all.json") == 0) {
+                                       code = 200;
+                                       debug(D_WEB_CLIENT_ACCESS, "%llu: Sending JSON list of all monitors of RRD_STATS...", w->id);
 
-                               w->data->contenttype = CT_APPLICATION_JSON;
-                               w->data->bytes = 0;
-                               rrd_stats_all_json(w->data);
-                       }
-                       else if(strcmp(tok, "netdata.conf") == 0) {
-                               code = 200;
-                               debug(D_WEB_CLIENT_ACCESS, "%llu: Sending netdata.conf ...", w->id);
+                                       w->response.data->contenttype = CT_APPLICATION_JSON;
+                                       buffer_flush(w->response.data);
+                                       rrd_stats_all_json(w->response.data);
+                               }
+                               else if(strcmp(tok, "netdata.conf") == 0) {
+                                       code = 200;
+                                       debug(D_WEB_CLIENT_ACCESS, "%llu: Sending netdata.conf ...", w->id);
 
-                               w->data->contenttype = CT_TEXT_PLAIN;
-                               w->data->bytes = 0;
-                               generate_config(w->data, 0);
-                       }
-                       else if(strcmp(tok, WEB_PATH_FILE) == 0) { // "file"
-                               tok = mystrsep(&url, "/?&");
-                               if(tok && *tok) code = mysendfile(w, tok);
+                                       w->response.data->contenttype = CT_TEXT_PLAIN;
+                                       buffer_flush(w->response.data);
+                                       generate_config(w->response.data, 0);
+                               }
                                else {
-                                       code = 400;
-                                       w->data->bytes = 0;
-                                       strcpy(w->data->buffer, "You have to give a filename to get.\r\n");
-                                       w->data->bytes = strlen(w->data->buffer);
+                                       char filename[FILENAME_MAX+1];
+                                       url = filename;
+                                       strncpy(filename, w->last_url, FILENAME_MAX);
+                                       filename[FILENAME_MAX] = '\0';
+                                       tok = mystrsep(&url, "?");
+                                       buffer_flush(w->response.data);
+                                       code = mysendfile(w, (tok && *tok)?tok:"/");
                                }
                        }
-                       else if(!tok[0]) {
-                               w->data->bytes = 0;
-                               code = mysendfile(w, "index.html");
-                       }
                        else {
-                               w->data->bytes = 0;
-                               code = mysendfile(w, tok);
+                               char filename[FILENAME_MAX+1];
+                               url = filename;
+                               strncpy(filename, w->last_url, FILENAME_MAX);
+                               filename[FILENAME_MAX] = '\0';
+                               tok = mystrsep(&url, "?");
+                               buffer_flush(w->response.data);
+                               code = mysendfile(w, (tok && *tok)?tok:"/");
                        }
-
                }
                else {
                        strcpy(w->last_url, "not a valid response");
 
-                       if(buf) debug(D_WEB_CLIENT_ACCESS, "%llu: Cannot understand '%s'.", w->id, buf);
+                       debug(D_WEB_CLIENT_ACCESS, "%llu: Cannot understand '%s'.", w->id, w->response.data->buffer);
 
                        code = 500;
-                       w->data->bytes = 0;
-                       strcpy(w->data->buffer, "I don't understand you...\r\n");
-                       w->data->bytes = strlen(w->data->buffer);
+                       buffer_flush(w->response.data);
+                       buffer_strcat(w->response.data, "I don't understand you...\r\n");
                }
 
                // free url_decode() buffer
-               if(pointer_to_free) free(pointer_to_free);
+               if(pointer_to_free) {
+                       free(pointer_to_free);
+                       pointer_to_free = NULL;
+               }
        }
-       else if(w->data->bytes > 8192) {
+       else if(w->response.data->len > TOO_BIG_REQUEST) {
                strcpy(w->last_url, "too big request");
 
-               debug(D_WEB_CLIENT_ACCESS, "%llu: Received request is too big.", w->id);
+               debug(D_WEB_CLIENT_ACCESS, "%llu: Received request is too big (%zd bytes).", w->id, w->response.data->len);
 
                code = 400;
-               w->data->bytes = 0;
-               strcpy(w->data->buffer, "Received request is too big.\r\n");
-               w->data->bytes = strlen(w->data->buffer);
+               buffer_flush(w->response.data);
+               buffer_sprintf(w->response.data, "Received request is too big  (%zd bytes).\r\n", w->response.data->len);
        }
        else {
                // wait for more data
@@ -738,19 +1411,16 @@ void web_client_process(struct web_client *w) {
                return;
        }
 
-       if(w->data->bytes > w->data->size) {
-               error("%llu: memory overflow encountered (size is %ld, written %ld).", w->data->size, w->data->bytes);
-       }
-
        gettimeofday(&w->tv_ready, NULL);
-       w->data->date = time(NULL);
-       w->data->sent = 0;
+       w->response.data->date = time(NULL);
+       w->response.sent = 0;
+       w->response.code = code;
 
        // prepare the HTTP response header
        debug(D_WEB_CLIENT, "%llu: Generating HTTP header with response %d.", w->id, code);
 
-       char *content_type_string = "";
-       switch(w->data->contenttype) {
+       char *content_type_string;
+       switch(w->response.data->contenttype) {
                case CT_TEXT_HTML:
                        content_type_string = "text/html; charset=utf-8";
                        break;
@@ -799,17 +1469,45 @@ void web_client_process(struct web_client *w) {
                        content_type_string = "application/font-woff";
                        break;
 
+               case CT_APPLICATION_FONT_WOFF2:
+                       content_type_string = "application/font-woff2";
+                       break;
+
                case CT_APPLICATION_VND_MS_FONTOBJ:
                        content_type_string = "application/vnd.ms-fontobject";
                        break;
 
+               case CT_IMAGE_PNG:
+                       content_type_string = "image/png";
+                       break;
+
+               case CT_IMAGE_JPG:
+                       content_type_string = "image/jpeg";
+                       break;
+
+               case CT_IMAGE_GIF:
+                       content_type_string = "image/gif";
+                       break;
+
+               case CT_IMAGE_XICON:
+                       content_type_string = "image/x-icon";
+                       break;
+
+               case CT_IMAGE_BMP:
+                       content_type_string = "image/bmp";
+                       break;
+
+               case CT_IMAGE_ICNS:
+                       content_type_string = "image/icns";
+                       break;
+
                default:
                case CT_TEXT_PLAIN:
                        content_type_string = "text/plain; charset=utf-8";
                        break;
        }
 
-       char *code_msg = "";
+       char *code_msg;
        switch(code) {
                case 200:
                        code_msg = "OK";
@@ -837,20 +1535,15 @@ void web_client_process(struct web_client *w) {
        }
 
        char date[100];
-       struct tm tm = *gmtime(&w->data->date);
-       strftime(date, sizeof(date), "%a, %d %b %Y %H:%M:%S %Z", &tm);
+       struct tm tmbuf, *tm = gmtime_r(&w->response.data->date, &tmbuf);
+       strftime(date, sizeof(date), "%a, %d %b %Y %H:%M:%S %Z", tm);
 
-       char custom_header[MAX_HTTP_HEADER_SIZE + 1] = "";
-       if(w->response_header[0])
-               strcpy(custom_header, w->response_header);
-
-       int headerlen = 0;
-       headerlen += snprintf(&w->response_header[headerlen], MAX_HTTP_HEADER_SIZE - headerlen,
+       buffer_sprintf(w->response.header_output,
                "HTTP/1.1 %d %s\r\n"
                "Connection: %s\r\n"
                "Server: NetData Embedded HTTP Server\r\n"
-               "Content-Type: %s\r\n"
                "Access-Control-Allow-Origin: *\r\n"
+               "Content-Type: %s\r\n"
                "Date: %s\r\n"
                , code, code_msg
                , w->keepalive?"keep-alive":"close"
@@ -858,50 +1551,78 @@ void web_client_process(struct web_client *w) {
                , date
                );
 
-       if(custom_header[0])
-               headerlen += snprintf(&w->response_header[headerlen], MAX_HTTP_HEADER_SIZE - headerlen, "%s", custom_header);
+       if(w->cookie[0]) {
+               buffer_sprintf(w->response.header_output,
+                  "Set-Cookie: %s\r\n",
+                  w->cookie);
+       }
 
-       if(w->mode == WEB_CLIENT_MODE_NORMAL) {
-               headerlen += snprintf(&w->response_header[headerlen], MAX_HTTP_HEADER_SIZE - headerlen,
+       if(w->mode == WEB_CLIENT_MODE_OPTIONS) {
+               buffer_strcat(w->response.header_output,
+                       "Access-Control-Allow-Methods: GET, OPTIONS\r\n"
+                       "Access-Control-Allow-Credentials: true\r\n"
+                       "Access-Control-Allow-Headers: Accept, X-Requested-With, Content-Type, Cookie\r\n"
+                       "Access-Control-Max-Age: 1209600\r\n" // 86400 * 14
+                       );
+       }
+
+       if(buffer_strlen(w->response.header))
+               buffer_strcat(w->response.header_output, buffer_tostring(w->response.header));
+
+       if(w->mode == WEB_CLIENT_MODE_NORMAL && (w->response.data->options & WB_CONTENT_NO_CACHEABLE)) {
+               buffer_sprintf(w->response.header_output,
                        "Expires: %s\r\n"
                        "Cache-Control: no-cache\r\n"
-                       , date
-                       );
+                       , date);
        }
-       else {
-               headerlen += snprintf(&w->response_header[headerlen], MAX_HTTP_HEADER_SIZE - headerlen,
+       else if(w->mode != WEB_CLIENT_MODE_OPTIONS) {
+               char edate[100];
+               time_t et = w->response.data->date + (86400 * 14);
+               struct tm etmbuf, *etm = gmtime_r(&et, &etmbuf);
+               strftime(edate, sizeof(edate), "%a, %d %b %Y %H:%M:%S %Z", etm);
+
+               buffer_sprintf(w->response.header_output,
+                       "Expires: %s\r\n"
                        "Cache-Control: public\r\n"
-                       );
+                       , edate);
        }
 
        // if we know the content length, put it
-       if(!w->zoutput && (w->data->bytes || w->data->rbytes))
-               headerlen += snprintf(&w->response_header[headerlen], MAX_HTTP_HEADER_SIZE - headerlen,
+       if(!w->response.zoutput && (w->response.data->len || w->response.rlen))
+               buffer_sprintf(w->response.header_output,
                        "Content-Length: %ld\r\n"
-                       , w->data->bytes?w->data->bytes:w->data->rbytes
+                       , w->response.data->len? w->response.data->len: w->response.rlen
                        );
-       else if(!w->zoutput)
+       else if(!w->response.zoutput)
                w->keepalive = 0;       // content-length is required for keep-alive
 
-       if(w->zoutput) {
-               headerlen += snprintf(&w->response_header[headerlen], MAX_HTTP_HEADER_SIZE - headerlen,
+       if(w->response.zoutput) {
+               buffer_strcat(w->response.header_output,
                        "Content-Encoding: gzip\r\n"
                        "Transfer-Encoding: chunked\r\n"
                        );
        }
 
-       headerlen += snprintf(&w->response_header[headerlen], MAX_HTTP_HEADER_SIZE - headerlen, "\r\n");
+       buffer_strcat(w->response.header_output, "\r\n");
 
        // disable TCP_NODELAY, to buffer the header
        int flag = 0;
-       if(setsockopt(w->ofd, IPPROTO_TCP, TCP_NODELAY, (char *) &flag, sizeof(int)) != 0) error("%llu: failed to disable TCP_NODELAY on socket.", w->id);
+       if(setsockopt(w->ofd, IPPROTO_TCP, TCP_NODELAY, (char *) &flag, sizeof(int)) != 0)
+               error("%llu: failed to disable TCP_NODELAY on socket.", w->id);
 
        // sent the HTTP header
-       debug(D_WEB_DATA, "%llu: Sending response HTTP header of size %d: '%s'", w->id, headerlen, w->response_header);
+       debug(D_WEB_DATA, "%llu: Sending response HTTP header of size %d: '%s'"
+                       , w->id
+                       , buffer_strlen(w->response.header_output)
+                       , buffer_tostring(w->response.header_output)
+                       );
 
-       bytes = send(w->ofd, w->response_header, headerlen, 0);
-       if(bytes != headerlen)
-               error("%llu: HTTP Header failed to be sent (I sent %d bytes but the system sent %d bytes).", w->id, headerlen, bytes);
+       bytes = send(w->ofd, buffer_tostring(w->response.header_output), buffer_strlen(w->response.header_output), 0);
+       if(bytes != (ssize_t) buffer_strlen(w->response.header_output))
+               error("%llu: HTTP Header failed to be sent (I sent %d bytes but the system sent %d bytes)."
+                               , w->id
+                               , buffer_strlen(w->response.header_output)
+                               , bytes);
        else {
                global_statistics_lock();
                global_statistics.bytes_sent += bytes;
@@ -913,18 +1634,22 @@ void web_client_process(struct web_client *w) {
        if(setsockopt(w->ofd, IPPROTO_TCP, TCP_NODELAY, (char *) &flag, sizeof(int)) != 0) error("%llu: failed to enable TCP_NODELAY on socket.", w->id);
 
        // enable sending immediately if we have data
-       if(w->data->bytes) w->wait_send = 1;
+       if(w->response.data->len) w->wait_send = 1;
        else w->wait_send = 0;
 
        // pretty logging
        switch(w->mode) {
+               case WEB_CLIENT_MODE_OPTIONS:
+                       debug(D_WEB_CLIENT, "%llu: Done preparing the OPTIONS response. Sending data (%d bytes) to client.", w->id, w->response.data->len);
+                       break;
+
                case WEB_CLIENT_MODE_NORMAL:
-                       debug(D_WEB_CLIENT, "%llu: Done preparing the response. Sending data (%d bytes) to client.", w->id, w->data->bytes);
+                       debug(D_WEB_CLIENT, "%llu: Done preparing the response. Sending data (%d bytes) to client.", w->id, w->response.data->len);
                        break;
 
                case WEB_CLIENT_MODE_FILECOPY:
-                       if(w->data->rbytes) {
-                               debug(D_WEB_CLIENT, "%llu: Done preparing the response. Will be sending data file of %d bytes to client.", w->id, w->data->rbytes);
+                       if(w->response.rlen) {
+                               debug(D_WEB_CLIENT, "%llu: Done preparing the response. Will be sending data file of %d bytes to client.", w->id, w->response.rlen);
                                w->wait_receive = 1;
 
                                /*
@@ -932,8 +1657,8 @@ void web_client_process(struct web_client *w) {
                                // this block of code can be commented, without anything missing.
                                // when it is commented, the program will copy the data using async I/O.
                                {
-                                       long len = sendfile(w->ofd, w->ifd, NULL, w->data->rbytes);
-                                       if(len != w->data->rbytes) error("%llu: sendfile() should copy %ld bytes, but copied %ld. Falling back to manual copy.", w->id, w->data->rbytes, len);
+                                       long len = sendfile(w->ofd, w->ifd, NULL, w->response.data->rbytes);
+                                       if(len != w->response.data->rbytes) error("%llu: sendfile() should copy %ld bytes, but copied %ld. Falling back to manual copy.", w->id, w->response.data->rbytes, len);
                                        else web_client_reset(w);
                                }
                                */
@@ -948,16 +1673,16 @@ void web_client_process(struct web_client *w) {
        }
 }
 
-long web_client_send_chunk_header(struct web_client *w, int len)
+long web_client_send_chunk_header(struct web_client *w, long len)
 {
        debug(D_DEFLATE, "%llu: OPEN CHUNK of %d bytes (hex: %x).", w->id, len, len);
        char buf[1024];
-       sprintf(buf, "%X\r\n", len);
-       int bytes = send(w->ofd, buf, strlen(buf), MSG_DONTWAIT);
+       sprintf(buf, "%lX\r\n", len);
+       ssize_t bytes = send(w->ofd, buf, strlen(buf), MSG_DONTWAIT);
 
        if(bytes > 0) debug(D_DEFLATE, "%llu: Sent chunk header %d bytes.", w->id, bytes);
        else if(bytes == 0) debug(D_DEFLATE, "%llu: Did not send chunk header to the client.", w->id);
-       else debug(D_DEFLATE, "%llu: Failed to send chunk header to client. Reason: %s", w->id, strerror(errno));
+       else debug(D_DEFLATE, "%llu: Failed to send chunk header to client.", w->id);
 
        return bytes;
 }
@@ -966,11 +1691,11 @@ long web_client_send_chunk_close(struct web_client *w)
 {
        //debug(D_DEFLATE, "%llu: CLOSE CHUNK.", w->id);
 
-       int bytes = send(w->ofd, "\r\n", 2, MSG_DONTWAIT);
+       ssize_t bytes = send(w->ofd, "\r\n", 2, MSG_DONTWAIT);
 
        if(bytes > 0) debug(D_DEFLATE, "%llu: Sent chunk suffix %d bytes.", w->id, bytes);
        else if(bytes == 0) debug(D_DEFLATE, "%llu: Did not send chunk suffix to the client.", w->id);
-       else debug(D_DEFLATE, "%llu: Failed to send chunk suffix to client. Reason: %s", w->id, strerror(errno));
+       else debug(D_DEFLATE, "%llu: Failed to send chunk suffix to client.", w->id);
 
        return bytes;
 }
@@ -979,39 +1704,39 @@ long web_client_send_chunk_finalize(struct web_client *w)
 {
        //debug(D_DEFLATE, "%llu: FINALIZE CHUNK.", w->id);
 
-       int bytes = send(w->ofd, "\r\n0\r\n\r\n", 7, MSG_DONTWAIT);
+       ssize_t bytes = send(w->ofd, "\r\n0\r\n\r\n", 7, MSG_DONTWAIT);
 
        if(bytes > 0) debug(D_DEFLATE, "%llu: Sent chunk suffix %d bytes.", w->id, bytes);
        else if(bytes == 0) debug(D_DEFLATE, "%llu: Did not send chunk suffix to the client.", w->id);
-       else debug(D_DEFLATE, "%llu: Failed to send chunk suffix to client. Reason: %s", w->id, strerror(errno));
+       else debug(D_DEFLATE, "%llu: Failed to send chunk suffix to client.", w->id);
 
        return bytes;
 }
 
-#ifndef NETDATA_WITHOUT_ZLIB
+#ifdef NETDATA_WITH_ZLIB
 long web_client_send_deflate(struct web_client *w)
 {
-       long bytes = 0, t = 0;
+       long len = 0, t = 0;
 
        // when using compression,
-       // w->data->sent is the amount of bytes passed through compression
+       // w->response.sent is the amount of bytes passed through compression
 
-       // debug(D_DEFLATE, "%llu: TEST w->data->bytes = %d, w->data->sent = %d, w->zhave = %d, w->zsent = %d, w->zstream.avail_in = %d, w->zstream.avail_out = %d, w->zstream.total_in = %d, w->zstream.total_out = %d.", w->id, w->data->bytes, w->data->sent, w->zhave, w->zsent, w->zstream.avail_in, w->zstream.avail_out, w->zstream.total_in, w->zstream.total_out);
+       debug(D_DEFLATE, "%llu: web_client_send_deflate(): w->response.data->len = %d, w->response.sent = %d, w->response.zhave = %d, w->response.zsent = %d, w->response.zstream.avail_in = %d, w->response.zstream.avail_out = %d, w->response.zstream.total_in = %d, w->response.zstream.total_out = %d.", w->id, w->response.data->len, w->response.sent, w->response.zhave, w->response.zsent, w->response.zstream.avail_in, w->response.zstream.avail_out, w->response.zstream.total_in, w->response.zstream.total_out);
 
-       if(w->data->bytes - w->data->sent == 0 && w->zstream.avail_in == 0 && w->zhave == w->zsent && w->zstream.avail_out != 0) {
+       if(w->response.data->len - w->response.sent == 0 && w->response.zstream.avail_in == 0 && w->response.zhave == w->response.zsent && w->response.zstream.avail_out != 0) {
                // there is nothing to send
 
                debug(D_WEB_CLIENT, "%llu: Out of output data.", w->id);
 
                // finalize the chunk
-               if(w->data->sent != 0)
+               if(w->response.sent != 0)
                        t += web_client_send_chunk_finalize(w);
 
                // there can be two cases for this
                // A. we have done everything
                // B. we temporarily have nothing to send, waiting for the buffer to be filled by ifd
 
-               if(w->mode == WEB_CLIENT_MODE_FILECOPY && w->wait_receive && w->ifd != w->ofd && w->data->rbytes && w->data->rbytes > w->data->bytes) {
+               if(w->mode == WEB_CLIENT_MODE_FILECOPY && w->wait_receive && w->ifd != w->ofd && w->response.rlen && w->response.rlen > w->response.data->len) {
                        // we have to wait, more data will come
                        debug(D_WEB_CLIENT, "%llu: Waiting for more data to become available.", w->id);
                        w->wait_send = 0;
@@ -1019,7 +1744,7 @@ long web_client_send_deflate(struct web_client *w)
                }
 
                if(w->keepalive == 0) {
-                       debug(D_WEB_CLIENT, "%llu: Closing (keep-alive is not enabled). %ld bytes sent.", w->id, w->data->sent);
+                       debug(D_WEB_CLIENT, "%llu: Closing (keep-alive is not enabled). %ld bytes sent.", w->id, w->response.sent);
                        errno = 0;
                        return(-1);
                }
@@ -1030,76 +1755,82 @@ long web_client_send_deflate(struct web_client *w)
                return(0);
        }
 
-       if(w->zstream.avail_out == 0 && w->zhave == w->zsent) {
+       if(w->response.zhave == w->response.zsent) {
                // compress more input data
 
                // close the previous open chunk
-               if(w->data->sent != 0) t += web_client_send_chunk_close(w);
+               if(w->response.sent != 0) t += web_client_send_chunk_close(w);
 
-               debug(D_DEFLATE, "%llu: Compressing %d bytes starting from %d.", w->id, (w->data->bytes - w->data->sent), w->data->sent);
+               debug(D_DEFLATE, "%llu: Compressing %d new bytes starting from %d (and %d left behind).", w->id, (w->response.data->len - w->response.sent), w->response.sent, w->response.zstream.avail_in);
 
                // give the compressor all the data not passed through the compressor yet
-               if(w->data->bytes > w->data->sent) {
-                       w->zstream.next_in = (Bytef *)&w->data->buffer[w->data->sent];
-                       w->zstream.avail_in = (w->data->bytes - w->data->sent);
+               if(w->response.data->len > w->response.sent) {
+#ifdef NETDATA_INTERNAL_CHECKS
+                       if((long)w->response.sent - (long)w->response.zstream.avail_in < 0)
+                               error("internal error: avail_in is corrupted.");
+#endif
+                       w->response.zstream.next_in = (Bytef *)&w->response.data->buffer[w->response.sent - w->response.zstream.avail_in];
+                       w->response.zstream.avail_in += (uInt) (w->response.data->len - w->response.sent);
                }
 
                // reset the compressor output buffer
-               w->zstream.next_out = w->zbuffer;
-               w->zstream.avail_out = ZLIB_CHUNK;
+               w->response.zstream.next_out = w->response.zbuffer;
+               w->response.zstream.avail_out = ZLIB_CHUNK;
 
                // ask for FINISH if we have all the input
                int flush = Z_SYNC_FLUSH;
                if(w->mode == WEB_CLIENT_MODE_NORMAL
-                       || (w->mode == WEB_CLIENT_MODE_FILECOPY && w->data->bytes == w->data->rbytes)) {
+                       || (w->mode == WEB_CLIENT_MODE_FILECOPY && !w->wait_receive && w->response.data->len == w->response.rlen)) {
                        flush = Z_FINISH;
-                       debug(D_DEFLATE, "%llu: Requesting Z_FINISH.", w->id);
+                       debug(D_DEFLATE, "%llu: Requesting Z_FINISH, if possible.", w->id);
                }
                else {
                        debug(D_DEFLATE, "%llu: Requesting Z_SYNC_FLUSH.", w->id);
                }
 
                // compress
-               if(deflate(&w->zstream, flush) == Z_STREAM_ERROR) {
+               if(deflate(&w->response.zstream, flush) == Z_STREAM_ERROR) {
                        error("%llu: Compression failed. Closing down client.", w->id);
                        web_client_reset(w);
                        return(-1);
                }
 
-               w->zhave = ZLIB_CHUNK - w->zstream.avail_out;
-               w->zsent = 0;
+               w->response.zhave = ZLIB_CHUNK - w->response.zstream.avail_out;
+               w->response.zsent = 0;
 
                // keep track of the bytes passed through the compressor
-               w->data->sent = w->data->bytes;
+               w->response.sent = w->response.data->len;
 
-               debug(D_DEFLATE, "%llu: Compression produced %d bytes.", w->id, w->zhave);
+               debug(D_DEFLATE, "%llu: Compression produced %d bytes.", w->id, w->response.zhave);
 
                // open a new chunk
-               t += web_client_send_chunk_header(w, w->zhave);
+               t += web_client_send_chunk_header(w, w->response.zhave);
        }
+       
+       debug(D_WEB_CLIENT, "%llu: Sending %d bytes of data (+%d of chunk header).", w->id, w->response.zhave - w->response.zsent, t);
 
-       bytes = send(w->ofd, &w->zbuffer[w->zsent], w->zhave - w->zsent, MSG_DONTWAIT);
-       if(bytes > 0) {
-               w->zsent += bytes;
-               if(t > 0) bytes += t;
-               debug(D_WEB_CLIENT, "%llu: Sent %d bytes.", w->id, bytes);
+       len = send(w->ofd, &w->response.zbuffer[w->response.zsent], (size_t) (w->response.zhave - w->response.zsent), MSG_DONTWAIT);
+       if(len > 0) {
+               w->response.zsent += len;
+               if(t > 0) len += t;
+               debug(D_WEB_CLIENT, "%llu: Sent %d bytes.", w->id, len);
        }
-       else if(bytes == 0) debug(D_WEB_CLIENT, "%llu: Did not send any bytes to the client.", w->id);
+       else if(len == 0) debug(D_WEB_CLIENT, "%llu: Did not send any bytes to the client (zhave = %ld, zsent = %ld, need to send = %ld).", w->id, w->response.zhave, w->response.zsent, w->response.zhave - w->response.zsent);
        else debug(D_WEB_CLIENT, "%llu: Failed to send data to client. Reason: %s", w->id, strerror(errno));
 
-       return(bytes);
+       return(len);
 }
-#endif // NETDATA_WITHOUT_ZLIB
+#endif // NETDATA_WITH_ZLIB
 
 long web_client_send(struct web_client *w)
 {
-#ifndef NETDATA_WITHOUT_ZLIB
-       if(likely(w->zoutput)) return web_client_send_deflate(w);
-#endif // NETDATA_WITHOUT_ZLIB
+#ifdef NETDATA_WITH_ZLIB
+       if(likely(w->response.zoutput)) return web_client_send_deflate(w);
+#endif // NETDATA_WITH_ZLIB
 
        long bytes;
 
-       if(unlikely(w->data->bytes - w->data->sent == 0)) {
+       if(unlikely(w->response.data->len - w->response.sent == 0)) {
                // there is nothing to send
 
                debug(D_WEB_CLIENT, "%llu: Out of output data.", w->id);
@@ -1108,7 +1839,7 @@ long web_client_send(struct web_client *w)
                // A. we have done everything
                // B. we temporarily have nothing to send, waiting for the buffer to be filled by ifd
 
-               if(w->mode == WEB_CLIENT_MODE_FILECOPY && w->wait_receive && w->ifd != w->ofd && w->data->rbytes && w->data->rbytes > w->data->bytes) {
+               if(w->mode == WEB_CLIENT_MODE_FILECOPY && w->wait_receive && w->ifd != w->ofd && w->response.rlen && w->response.rlen > w->response.data->len) {
                        // we have to wait, more data will come
                        debug(D_WEB_CLIENT, "%llu: Waiting for more data to become available.", w->id);
                        w->wait_send = 0;
@@ -1116,7 +1847,7 @@ long web_client_send(struct web_client *w)
                }
 
                if(unlikely(w->keepalive == 0)) {
-                       debug(D_WEB_CLIENT, "%llu: Closing (keep-alive is not enabled). %ld bytes sent.", w->id, w->data->sent);
+                       debug(D_WEB_CLIENT, "%llu: Closing (keep-alive is not enabled). %ld bytes sent.", w->id, w->response.sent);
                        errno = 0;
                        return(-1);
                }
@@ -1126,13 +1857,13 @@ long web_client_send(struct web_client *w)
                return(0);
        }
 
-       bytes = send(w->ofd, &w->data->buffer[w->data->sent], w->data->bytes - w->data->sent, MSG_DONTWAIT);
+       bytes = send(w->ofd, &w->response.data->buffer[w->response.sent], w->response.data->len - w->response.sent, MSG_DONTWAIT);
        if(likely(bytes > 0)) {
-               w->data->sent += bytes;
+               w->response.sent += bytes;
                debug(D_WEB_CLIENT, "%llu: Sent %d bytes.", w->id, bytes);
        }
        else if(likely(bytes == 0)) debug(D_WEB_CLIENT, "%llu: Did not send any bytes to the client.", w->id);
-       else debug(D_WEB_CLIENT, "%llu: Failed to send data to client. Reason: %s", w->id, strerror(errno));
+       else debug(D_WEB_CLIENT, "%llu: Failed to send data to client.", w->id);
 
        return(bytes);
 }
@@ -1140,27 +1871,27 @@ long web_client_send(struct web_client *w)
 long web_client_receive(struct web_client *w)
 {
        // do we have any space for more data?
-       web_buffer_increase(w->data, WEB_DATA_LENGTH_INCREASE_STEP);
+       buffer_need_bytes(w->response.data, WEB_REQUEST_LENGTH);
 
-       long left = w->data->size - w->data->bytes;
+       long left = w->response.data->size - w->response.data->len;
        long bytes;
 
        if(unlikely(w->mode == WEB_CLIENT_MODE_FILECOPY))
-               bytes = read(w->ifd, &w->data->buffer[w->data->bytes], (left-1));
+               bytes = read(w->ifd, &w->response.data->buffer[w->response.data->len], (size_t) (left - 1));
        else
-               bytes = recv(w->ifd, &w->data->buffer[w->data->bytes], left-1, MSG_DONTWAIT);
+               bytes = recv(w->ifd, &w->response.data->buffer[w->response.data->len], (size_t) (left - 1), MSG_DONTWAIT);
 
        if(likely(bytes > 0)) {
-               int old = w->data->bytes;
-               w->data->bytes += bytes;
-               w->data->buffer[w->data->bytes] = '\0';
+               size_t old = w->response.data->len;
+               w->response.data->len += bytes;
+               w->response.data->buffer[w->response.data->len] = '\0';
 
                debug(D_WEB_CLIENT, "%llu: Received %d bytes.", w->id, bytes);
-               debug(D_WEB_DATA, "%llu: Received data: '%s'.", w->id, &w->data->buffer[old]);
+               debug(D_WEB_DATA, "%llu: Received data: '%s'.", w->id, &w->response.data->buffer[old]);
 
                if(w->mode == WEB_CLIENT_MODE_FILECOPY) {
                        w->wait_send = 1;
-                       if(w->data->rbytes && w->data->bytes >= w->data->rbytes) w->wait_receive = 0;
+                       if(w->response.rlen && w->response.data->len >= w->response.rlen) w->wait_receive = 0;
                }
        }
        else if(likely(bytes == 0)) {
@@ -1247,19 +1978,19 @@ void *web_client_main(void *ptr)
                }
 
                if(FD_ISSET(w->ifd, &efds)) {
-                       debug(D_WEB_CLIENT_ACCESS, "%llu: Received error on input socket (%s).", w->id, strerror(errno));
+                       debug(D_WEB_CLIENT_ACCESS, "%llu: Received error on input socket.", w->id);
                        break;
                }
 
                if(FD_ISSET(w->ofd, &efds)) {
-                       debug(D_WEB_CLIENT_ACCESS, "%llu: Received error on output socket (%s).", w->id, strerror(errno));
+                       debug(D_WEB_CLIENT_ACCESS, "%llu: Received error on output socket.", w->id);
                        break;
                }
 
                if(w->wait_send && FD_ISSET(w->ofd, &ofds)) {
                        long bytes;
                        if((bytes = web_client_send(w)) < 0) {
-                               debug(D_WEB_CLIENT, "%llu: Cannot send data to client. Closing client (ouput: %s).", w->id, strerror(errno));
+                               debug(D_WEB_CLIENT, "%llu: Cannot send data to client. Closing client.", w->id);
                                errno = 0;
                                break;
                        }
@@ -1272,19 +2003,20 @@ void *web_client_main(void *ptr)
                if(w->wait_receive && FD_ISSET(w->ifd, &ifds)) {
                        long bytes;
                        if((bytes = web_client_receive(w)) < 0) {
-                               debug(D_WEB_CLIENT, "%llu: Cannot receive data from client. Closing client (input: %s).", w->id, strerror(errno));
+                               debug(D_WEB_CLIENT, "%llu: Cannot receive data from client. Closing client.", w->id);
                                errno = 0;
                                break;
                        }
 
-                       global_statistics_lock();
-                       global_statistics.bytes_received += bytes;
-                       global_statistics_unlock();
-
                        if(w->mode == WEB_CLIENT_MODE_NORMAL) {
-                               debug(D_WEB_CLIENT, "%llu: Attempting to process received data.", w->id);
+                               debug(D_WEB_CLIENT, "%llu: Attempting to process received data (%ld bytes).", w->id, bytes);
+                               // info("%llu: Attempting to process received data (%ld bytes).", w->id, bytes);
                                web_client_process(w);
                        }
+
+                       global_statistics_lock();
+                       global_statistics.bytes_received += bytes;
+                       global_statistics_unlock();
                }
        }